process for the production of alkyl - and when a person in alpha cyanoacrylaten by depolymerisierung of poly (alkyl alpha cyanoacrylaten) or poly (when a person in alpha cyanoacrylaten) and its use as an industrial and / or medical glue

摘要

This invenu00c7u00c3o refers to the preparation of alpha cyanoacrylate alkyl or alcoxialquilo in the form monomu00c9rica, despolimerizau00c7u00c3o corresponding poly (alpha - cyanoacrylate alkyl or alcoxialquilo) (PCA). The PCA are preferably obtained by condensau00c7u00c3o a cianoacetato with formaldehyde (or a polu00cdmero last), catalyzed by alkali compounds.According to the invenu00c7u00c3o, the product of the condensau00c7u00c3o, polu00cd (alpha cu00cdanoacrilato alkyl or alcoxialquilo), is mixed with a system of despolimerizau00c7u00c3o comprising phosphorus pentu00d3xido of P2O5, hydroquinone, acid ortho fosfu00d3rico and acid to - toluenossulfu00d3nico.This process is performed in a reactor descontu00cdnuo with a capacitor, heated to a temperature between 100 to 300 C, under an atmosphere of vacuum of 0.5 to 50 Torr (7x10 - 5 - 7x10 - 3 MPa) and leads to alpha cyanoacrylate alkyl or alcoxialquilo monomu00c9ricos, stable in both phases of gas and lu00cdqu IDA.After an additional purification by distillation under vacuum, the cyanoacrylate adhesive or may be used as clinical technical rapid setting. The application of the system of despolimerizau00c7u00c3o four components mentioned above eliminates the need to use a stream of sulphur dioxide in the reactor during the despolimerizau00c7u00c3o, to stabilize the resulting monomer.In addition, this system makes use of a despolimerizau00c7u00c3o dispensu00c1vel means for transfer of heat with high boiling point, to keep the PCA liquid while it is depolymd.As a result, are produced alpha cyanoacrylate alkyl or alcoxu00cdalquu00cdlo high purity, high yield, without the use of hazardous gases, thereby simplifying the design of the reactor and reducing the formation of waste liquids.